<?php
/**
 * Zend Framework
 * LICENSE
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 * @category Zend
 * @package Zend_Mail
 * @subpackage Storage
 * @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
 * @license http://framework.zend.com/license/new-bsd New BSD License
 * @version $Id: Mbox.php 24593 2012-01-05 20:35:02Z matthew $
 */
/**
 *
 * @see Zend_Loader May be used in constructor, but commented out for now
 */
// require_once 'Zend/Loader.php';
/**
 *
 * @see Zend_Mail_Storage_Abstract
 */
require_once 'Zend/Mail/Storage/Abstract.php';
/**
 *
 * @see Zend_Mail_Message_File
 */
require_once 'Zend/Mail/Message/File.php';

/**
 *
 * @category Zend
 * @package Zend_Mail
 * @subpackage Storage
 * @copyright Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
 * @license http://framework.zend.com/license/new-bsd New BSD License
 */
class Zend_Mail_Storage_Mbox extends Zend_Mail_Storage_Abstract {

    /**
     * file handle to mbox file
     * @var null resource
     */
    protected $_fh;

    /**
     * filename of mbox file for __wakeup
     * @var string
     */
    protected $_filename;

    /**
     * modification date of mbox file for __wakeup
     * @var int
     */
    protected $_filemtime;

    /**
     * start and end position of messages as array('start' => start, 'seperator' => headersep, 'end' => end)
     * @var array
     */
    protected $_positions;

    /**
     * used message class, change it in an extened class to extend the returned message class
     * @var string
     */
    protected $_messageClass = 'Zend_Mail_Message_File';

    /**
     * Count messages all messages in current box
     * @return int number of messages
     * @throws Zend_Mail_Storage_Exception
     */
    public function countMessages () {
        return count ($this -> _positions);
    }

    /**
     * Get a list of messages with number and size
     * @param int|null $id number of message or null for all messages
     * @return int array of given message of list with all messages as array(num => size)
     */
    public function getSize ($id = 0) {
        if ($id) {
            $pos = $this -> _positions[$id - 1];
            return $pos['end'] - $pos['start'];
        }
        $result = array();
        foreach ($this -> _positions as $num => $pos) {
            $result[$num + 1] = $pos['end'] - $pos['start'];
        }
        return $result;
    }

    /**
     * Get positions for mail message or throw exeption if id is invalid
     * @param int $id number of message
     * @return array positions as in _positions
     * @throws Zend_Mail_Storage_Exception
     */
    protected function _getPos ($id) {
        if ( ! isset ($this -> _positions[$id - 1])) {
            /**
             *
             * @see Zend_Mail_Storage_Exception
             */
            require_once 'Zend/Mail/Storage/Exception.php';
            throw new Zend_Mail_Storage_Exception ('id does not exist');
        }
        return $this -> _positions[$id - 1];
    }

    /**
     * Fetch a message
     * @param int $id number of message
     * @return Zend_Mail_Message_File
     * @throws Zend_Mail_Storage_Exception
     */
    public function getMessage ($id) {
        // TODO that's ugly, would be better to let the message class decide
        if (strtolower ($this -> _messageClass) == 'zend_mail_message_file' || is_subclass_of ($this -> _messageClass, 'zend_mail_message_file')) {
            // TODO top/body lines
            $messagePos = $this -> _getPos ($id);
            return new $this -> _messageClass (array('file' => $this -> _fh, 'startPos' => $messagePos['start'], 'endPos' => $messagePos['end']));
        }
        $bodyLines = 0; // TODO: need a way to change that
        $message = $this -> getRawHeader ($id);
        // file pointer is after headers now
        if ($bodyLines) {
            $message .= "\n";
            while ($bodyLines --  && ftell ($this -> _fh) < $this -> _positions[$id - 1]['end']) {
                $message .= fgets ($this -> _fh);
            }
        }
        return new $this -> _messageClass (array('handler' => $this, 'id' => $id, 'headers' => $message));
    }
    /*
     * Get raw header of message or part @param int $id number of message @param null|array|string $part path to part or null for messsage header @param int $topLines include this many lines with header (after an empty line) @return string raw header @throws Zend_Mail_Protocol_Exception @throws Zend_Mail_Storage_Exception
     */
    public function getRawHeader ($id, $part = null, $topLines = 0) {
        if ($part !== null) {
            // TODO: implement
            /**
             *
             * @see Zend_Mail_Storage_Exception
             */
            require_once 'Zend/Mail/Storage/Exception.php';
            throw new Zend_Mail_Storage_Exception ('not implemented');
        }
        $messagePos = $this -> _getPos ($id);
        // TODO: toplines
        return stream_get_contents ($this -> _fh, $messagePos['separator'] - $messagePos['start'], $messagePos['start']);
    }
    /*
     * Get raw content of message or part @param int $id number of message @param null|array|string $part path to part or null for messsage content @return string raw content @throws Zend_Mail_Protocol_Exception @throws Zend_Mail_Storage_Exception
     */
    public function getRawContent ($id, $part = null) {
        if ($part !== null) {
            // TODO: implement
            /**
             *
             * @see Zend_Mail_Storage_Exception
             */
            require_once 'Zend/Mail/Storage/Exception.php';
            throw new Zend_Mail_Storage_Exception ('not implemented');
        }
        $messagePos = $this -> _getPos ($id);
        return stream_get_contents ($this -> _fh, $messagePos['end'] - $messagePos['separator'], $messagePos['separator']);
    }

    /**
     * Create instance with parameters
     * Supported parameters are:
     * - filename filename of mbox file
     * @param array $params mail reader specific parameters
     * @throws Zend_Mail_Storage_Exception
     */
    public function __construct ($params) {
        if (is_array ($params)) {
            $params = (object) $params;
        }
        if ( ! isset ($params -> filename) /* || Zend_Loader::isReadable($params['filename']) */) {
            /**
             *
             * @see Zend_Mail_Storage_Exception
             */
            require_once 'Zend/Mail/Storage/Exception.php';
            throw new Zend_Mail_Storage_Exception ('no valid filename given in params');
        }
        $this -> _openMboxFile ($params -> filename);
        $this -> _has['top'] = true;
        $this -> _has['uniqueid'] = false;
    }

    /**
     * check if given file is a mbox file
     * if $file is a resource its file pointer is moved after the first line
     * @param resource|string $file stream resource of name of file
     * @param bool $fileIsString file is string or resource
     * @return bool file is mbox file
     */
    protected function _isMboxFile ($file, $fileIsString = true) {
        if ($fileIsString) {
            $file = @fopen ($file, 'r');
            if ( ! $file) {
                return false;
            }
        } else {
            fseek ($file, 0);
        }
        $result = false;
        $line = fgets ($file);
        if (strpos ($line, 'From ') === 0) {
            $result = true;
        }
        if ($fileIsString) {
            @fclose ($file);
        }
        return $result;
    }

    /**
     * open given file as current mbox file
     * @param string $filename filename of mbox file
     * @return null
     * @throws Zend_Mail_Storage_Exception
     */
    protected function _openMboxFile ($filename) {
        if ($this -> _fh) {
            $this -> close ();
        }
        $this -> _fh = @fopen ($filename, 'r');
        if ( ! $this -> _fh) {
            /**
             *
             * @see Zend_Mail_Storage_Exception
             */
            require_once 'Zend/Mail/Storage/Exception.php';
            throw new Zend_Mail_Storage_Exception ('cannot open mbox file');
        }
        $this -> _filename = $filename;
        $this -> _filemtime = filemtime ($this -> _filename);
        if ( ! $this -> _isMboxFile ($this -> _fh, false)) {
            @fclose ($this -> _fh);
            /**
             *
             * @see Zend_Mail_Storage_Exception
             */
            require_once 'Zend/Mail/Storage/Exception.php';
            throw new Zend_Mail_Storage_Exception ('file is not a valid mbox format');
        }
        $messagePos = array('start' => ftell ($this -> _fh), 'separator' => 0, 'end' => 0);
        while (($line = fgets ($this -> _fh)) !== false) {
            if (strpos ($line, 'From ') === 0) {
                $messagePos['end'] = ftell ($this -> _fh) - strlen ($line) - 2; // + newline
                if ( ! $messagePos['separator']) {
                    $messagePos['separator'] = $messagePos['end'];
                }
                $this -> _positions[] = $messagePos;
                $messagePos = array('start' => ftell ($this -> _fh), 'separator' => 0, 'end' => 0);
            }
            if ( ! $messagePos['separator'] &&  ! trim ($line)) {
                $messagePos['separator'] = ftell ($this -> _fh);
            }
        }
        $messagePos['end'] = ftell ($this -> _fh);
        if ( ! $messagePos['separator']) {
            $messagePos['separator'] = $messagePos['end'];
        }
        $this -> _positions[] = $messagePos;
    }

    /**
     * Close resource for mail lib.
     * If you need to control, when the resource
     * is closed. Otherwise the destructor would call this.
     * @return void
     */
    public function close () {
        @fclose ($this -> _fh);
        $this -> _positions = array();
    }

    /**
     * Waste some CPU cycles doing nothing.
     * @return void
     */
    public function noop () {
        return true;
    }

    /**
     * stub for not supported message deletion
     * @return null
     * @throws Zend_Mail_Storage_Exception
     */
    public function removeMessage ($id) {
        /**
         *
         * @see Zend_Mail_Storage_Exception
         */
        require_once 'Zend/Mail/Storage/Exception.php';
        throw new Zend_Mail_Storage_Exception ('mbox is read-only');
    }

    /**
     * get unique id for one or all messages
     * Mbox does not support unique ids (yet) - it's always the same as the message number.
     * That shouldn't be a problem, because we can't change mbox files. Therefor the message
     * number is save enough.
     * @param int|null $id message number
     * @return array string number for given message or all messages as array
     * @throws Zend_Mail_Storage_Exception
     */
    public function getUniqueId ($id = null) {
        if ($id) {
            // check if id exists
            $this -> _getPos ($id);
            return $id;
        }
        $range = range (1, $this -> countMessages ());
        return array_combine ($range, $range);
    }

    /**
     * get a message number from a unique id
     * I.e.
     * if you have a webmailer that supports deleting messages you should use unique ids
     * as parameter and use this method to translate it to message number right before calling removeMessage()
     * @param string $id unique id
     * @return int message number
     * @throws Zend_Mail_Storage_Exception
     */
    public function getNumberByUniqueId ($id) {
        // check if id exists
        $this -> _getPos ($id);
        return $id;
    }

    /**
     * magic method for serialize()
     * with this method you can cache the mbox class
     * @return array name of variables
     */
    public function __sleep () {
        return array('_filename', '_positions', '_filemtime');
    }

    /**
     * magic method for unserialize()
     * with this method you can cache the mbox class
     * for cache validation the mtime of the mbox file is used
     * @return null
     * @throws Zend_Mail_Storage_Exception
     */
    public function __wakeup () {
        if ($this -> _filemtime != @filemtime ($this -> _filename)) {
            $this -> close ();
            $this -> _openMboxFile ($this -> _filename);
        } else {
            $this -> _fh = @fopen ($this -> _filename, 'r');
            if ( ! $this -> _fh) {
                /**
                 *
                 * @see Zend_Mail_Storage_Exception
                 */
                require_once 'Zend/Mail/Storage/Exception.php';
                throw new Zend_Mail_Storage_Exception ('cannot open mbox file');
            }
        }
    }

}
